Slab piling system

ABSTRACT

A platform for use with a steel mill on which to stack steel plate or billets is provided with hydraulic rams to raise and lower the platform, and has a pair of pivoting side links to stabilize the platform against side thrust when billets are slid thereon, the stability of the platform against canting being provided by a downwardly extending moment arm having a pivotal linkage attached to the bottom and thereof, and a synchronizing shaft connecting a pair of the stabilizing linkages to prevent relative twisting therebetween.

United States Patent [191 Field 1 SLAB FILING SYSTEM [75] Inventor:Michael Frank Field, Sydney, Nova Scotia, Canada [73] Assignee: DominionEngineering Works,

Limited, Lachine, Quebec, Canada 22 Filed: June 25,1973

211 Appl. No.: 373,541

[30] Foreign Application Priority Data Aug. 28, 1972 Canada 150321 [52]US. Cl. 254/124, 254/10 C [51] Int. Cl B661 3/00 [58] Field of Search181/8.72, 8.71; 254/10 R, 254/10 A, 10 B, 10 C, 124; 271/215 [56]References Cited UNITED STATES PATENTS 2,790,683 4/1957 Clark 254/10 R X[451 Aug.20,1974

2,906,497 9/1959 Wolf 254/10 B 3,111,232 11/1963 Benson 254/124 X3,334,895 8/1967 Daniels et al. 271/215 X Primary ExaminerRobert B.Reeves Assistant Examiner-Hadd Lane Attorney, Agent, or Firml-lenry C.Westin; Daniel Patch 57 ABSTRACT 3 Claims, 2 Drawing Figures vSLABFILING SYSTEM This invention is directed to a load elevator, and inparticular to an elevator for stacking steel slab s in a steel mill.

In the operation of a steel mill, slabs moving along the roll tables areassembled in stacks for pick-up and transportation by crane. Thestacking of the slabs is normally effected using a slabelevatorpositioned beside the roll table, with slab pushers being usedto slide the slabs sequentially onto the elevator and the height of theelevator being progressively reduced by the thickness of the slab toensure easy slide-on of the succeeding slab.

The slab elevators of the prior art generally use mechanical rams drivenby threaded nuts, the application of transverse forces being resisted byslide guides.

Owing to the adverse nature of mill environment,

such as high temperatures and'in particular the presence of scale, etc.the prior art mechanisms are very subject to undue wear, while at thesame time having a high initial cost. The operation of such prior artarrangement is further complicated by the necessity of synchronizing theindividual drives to the raising spindles in order to prevent canting ofthe elevator platform.

The present invention provides a simple robust platform elevator usinghydraulic rams to control the elevation of the platform. Pivoted linksthat are substantially immune to adverse mill conditions are used toprovide transverse restraint of the platform under loading forces and tostabilize the platform against canting and tipping.

In addition to providing simple robust mechanisms that are substantiallyunaffected by mill conditions, the present invention provides platforminstallation system of very low cost, in that hydraulic jacks suitablefor this use are not a high-cost item, and the energizing requirementfor raising the platform can be met by the use of an electric motor andpump of comparatively small size in combination with a suitable pressureaccumulator.

In addition to the foregoing advantages, in operation the presentinvention has the particular attribute that the rate of lowering of theplatform for the reception of a further plate or billet is dependentonly upon the function of the control valve through which the hydraulicrams are bled to drain. Thus, the capability of rapid realignment of thetop surface of a plate on the loaded platform with the surface of thetable rolls ensures a minimum delay in the transference of slabssuccessively to the piler.

The present invention thus provides platform apparatus for verticallypositioning heavy loads, comprising: substantially rigid platform meanshaving a top surface to receive a load thereon in lateral slidingrelation from a loading surface located adjacent one side of theplatform means; pivotal lateral restraint means securing the platformmeans in lateral positioned relation relative to the loading surface;adjustable lift means to provide upward support and displacement forceto the platform means in load bearing relation therewith; andstabilizing moment applying means to maintain the platform meanssubstantially level between an upper and a lower support position.

The present invention further provides a platform apparatus includingstabilizingmeans having a first moment applying means to precluderotation of the platform means about a first axis, and second momentapplying means to preclude rotation of the platform means about a secondaxis extending normal to the first axis in a horizontal plane.

The invention further provides a hydraulically elevated platform havinga moment arm extending downwardly from the platform, the lower endthereof having a pivotal restraint linkage attached thereto to maintainmotion of the arm along a substantially vertical path. Certainembodiments of the present invention are described, reference being madeto the accompanying drawings wherein:

FIG. 1 is an end elevation in partial section of an elevator platformaccording to the present invention; and

FIG. 2 is a side elevation of the elevator platform.

Referring first to FIG. 1, the elevator arrangement I0 is showninstalled in relation to a portion of a roll table 12 having rolls 14extending beside the elevator 10 by means of which a slab 16 can bepositioned adjacent the elevator platform. Such a slab 16 shown chaindotted is illustrated as having been slid sideways partially off therolls 14 in loading relation-towards the elevator 10, shown chain dottedin its uppermost raised position, having the upper faces 18 of the tableribs 20 in horizontally aligned relation with the rolls 14 of the rolltable.

The elevator platform 22 comprises a plurality of ribs 20 carried by adeep section 24 having a top flange plate 26, bottom flange plate 28 anda plurality of web plates 30 extending therebetween. The spaced ribs 20permit the use of a crane C-hook in off-loading or loading the elevator,the lower jaw of such a hook being free to entertransversely betweenadjacent ones of the ribs 20 in lifting relation against the bottomsurface of a plate 16 supported by the rib surface 18.

A pair of lateral thrust links 32 are secured to a torque shaft 34carried between bearings 36, and connected at pivot pins 38 to restraintlugs 40 which in turn are secured to the bottom flange plate 28 of thestructure 24. A pair of extensible hydraulic rams 44 are pivotallymounted on gimbal pins 46 at about the midpoint of the length of rams44, and pivotally attached at 48 to a jack lug 50 attached to the bottomsurface of flange plate 28. The gimbal pins 46 are carried in bearings47 on a pad 49.

Admission of pressurized hydraulic fluid in usual well-known fashionfrom hydraulic pump means, not shown, causes controlled raising of theplatform 22. Controlled bleeding or exhaust of the hydraulic fluidprovides rapid lowering of the platform 22. A downwardly extendingtapered moment arm 52 of a deep T- section connects the platform 22 witha wish bone restraint link means 54, the wish bone links 54 beingpivotally pinned at 56 to the moment arm 52, and attached by pivotbrackets 58 and pins 60 to a suitable foundation or bolster.

The wish bone links 54 are substantially the same length as the thrustlinks 32 and positioned substantially parallel therewith, so that theplatform rises level, through a slight arc, with the links 32, 54 beingsubstantially horizontal at the mid-lift position. In operation the edgeto edge alignment of successive plates can be maintained by controllingthe stroke of the plate pushers (not shown).

The torque shaft 34 serves to stabilize the platform 22 against rocking.It will be understood that this equivalent stabilization function couldbe served, at least in part by the wish bone links 54 or modificationsthereof. Owing to the location of all working parts beneath the platform22 and the extensive use of pivotted restraint means the subjectelevator is highly resistant to damage from plate scale, while thesynchronized operation of the twin rams 44 is relatively easilymaintained.

In accordance with the provisions of the patent statutes, l haveexplained the principle and operation of my invention and haveillustrated and described what I tical displacement force to saidplatform means in direct load bearing relation therewith; a stabilizingrigid moment arm projecting downwardly from the platform means;restraint link means pivotally connected with the lower end of saidstabilizing arm, and a torque shaft securing said pair of links inmutual parallel relation to maintain said platform means substantiallylevel be tween an upper and a lower support position.

2. The apparatus as claimed in claim 1 wherein said torque shaft issecured between said pair of links outboard of said platform means.

3. Platform apparatus as claimed in claim 1 having said jack meanspivotally connected to said platform means on substantially the centralaxis thereof, said pair of restraint links being connected to saidplatform means on the side thereof remote from said loading surface,said pair of links and said restraint link means being of substantiallyequal length and arranged in substantially mutual parallel relation.

1. Platform apparatus for vertically positioning heavy loads,comprising: substantially rigid platform means of deep section having atop surface to receive a steel slab thereon in lateral sliding relationfrom a loading surface located adjacent one side of said platform means;a pair of pivotal lateral restraint links securing the platform means inlateral positioned relation relative to said load surface; adjustablehydraulic jack means extending upwardly in direct supporting relationwith said platform means to provide upward support and substantiallyvertical displacement force to said platform means in direct loadbearing relation therewith; a stabilizing rigid moment arm projectingdownwardly from the platform means; restraint link means pivotallyconnected with the lower end of said stabilizing arm, and a torque shaftsecuring said pair of links in mutual parallel relation to maintain saidplatform means substantially level between an upper and a lower supportposition.
 2. The apparatus as claimed in claim 1 wherein said torqueshaft is secured between said pair of links outboard of said platformmeans.
 3. Platform apparatus as claimed in claim 1 having said jackmeans pivotally connected to said platform means on substantially thecentral axis thereof, said pair of restraint links being connected tosaid platform means on the side thereof remote from said loadingsurface, said pair of links and said restraint link means being ofsubstantially equal length and arranged in substantially mutual parallelrelation.